11TH STREET BRIDGES, WASHINGTON DC Case Study Introduction Project Overview The District Department of Transportation (DDOT) and the Federal Highway Administration (FHWA) initiated the 11th Street Bridges project in 2005 to improve the highway connection between the Southeast/Southwest Freeway (I‐695) and the Anacostia Freeway (I‐295 and DC‐295) in southeast Washington DC. The project study area is shown in Figure 1. The project was to replace obsolete infrastructure, provide missing freeway connections to improve traffic flow to and from downtown Washington DC, discourage cut‐through traffic on neighborhood streets, improve local access, and better link land uses across the Anacostia River. Figure 1: Map of the 11th Street Bridges study area 1 When the Southeast/Southwest Freeway was built in the mid‐1960s, regional plans expected it to extend across the river and then join the Anacostia Freeway. However, those plans were abandoned, and today there is no direct connection between the Southeast/Southwest Freeway and the Anacostia Freeway to the north of the 11th Street Bridge complex. Traffic, therefore, is forced to use neighborhood streets to access the 11th Street Bridge complex and cross the Anacostia River. The result is increased traffic on local neighborhood streets, such as Martin Luther King, Jr. Avenue, Good Hope Road, Pennsylvania Avenue, and Minnesota Avenue. The 11th Street Bridge/Anacostia Freeway interchange does not allow traffic east of the Anacostia River to enter the Anacostia Freeway at this location. Drivers may cross the 11th Street Bridge toward downtown Washington DC or return, but they cannot enter or leave the Anacostia Freeway without taking neighborhood streets to adjacent interchanges at Pennsylvania Avenue, Howard Road, or South Capitol Street. Because the project involves reconfiguring the ramps on either shore but does not involve adding capacity to the freeway system, the project termini are where the ramps merge back into the existing freeway. DDOT and FHWA signed the Draft Environmental Impact Statement (DEIS) in June 2006, the Final Environmental Impact Statement (FEIS) in September 2008, and the Record of Decision in July 2009. Construction of the $300 project is now under way (as of March 2010). Planning History million The 11th Street Bridges project is a key component in District of Columbia’s plans to revitalize the Anacostia riverfront. In March 2000, federal and District agencies signed an agreement forming the Anacostia Waterfront Initiative (AWI) to transform the Anacostia River into a revitalized urban waterfront. The AWI brought together 20 federal and District agencies that own or control land along the Anacostia River to sign the AWI Memorandum of Understanding, creating a partnership between the federal and District governments to transform the Anacostia River waterfront. With Washington DC’s downtown nearly built out, the city is growing eastward toward and across the Anacostia River. The District is committed to recentering its growth along the Anacostia River and improving long‐neglected parks, environmental features, and infrastructure in the area. The 11th Street Bridges project falls within the context of the AWI and other planning activities within the project area. The AWI fostered a number of transportation studies, one of which was the Middle Anacostia River Crossings Transportation Study (MAC Study). The study was undertaken to evaluate traffic conditions and to recommend options to improve bridge and bridge and roadway connections between the 11th Street and John Philip Sousa Bridges to enhance mobility on both sides of Anacostia River. The study proposed several short‐ and long‐term improvements that include completing the 11th Street Bridge ramps to I‐295, reestablishing Barney Circle as an actual circle, separating the interstate (regional) traffic from the local traffic, riverfront access improvements, signage improvements, and pedestrian improvements. The findings and recommendations in the MAC Study formed the basis of the 11th Street Bridges’ alternative development and evaluation process. Purpose and Need The purpose of the 11th Street Bridges Project is fourfold: Reduce congestion and improve the mobility of traffic across the Anacostia River on the 11th Street Bridges and on the local streets in the area. Increase the safety of vehicular, pedestrian, and bicycle traffic in the Anacostia neighborhood. Replace deficient infrastructure and roadway design. Provide an alternative evacuation route and routes for security movements in and out of the nation’s capital. The following transportation needs are to be met by the project: 2 Improve Access and Reduce Congestion—Provide missing access to the Anacostia Freeway. Reduce volume of freeway traffic that spills onto the neighborhood streets due to current traffic patterns. Enhance Safety—Provide safe pedestrian and bicycle access across the river and to the Anacostia waterfront. Correct roadway design elements that reduce safety and result in congestion. Reduce number of vehicular crashes in the project interchanges. Correct Design Deficiencies—Replace bridges that are functionally and structurally obsolete. Improve signage in the project area to reduce confusion. Augment Homeland Security—Upgrade evacuation route for the nation’s capital and area military installations. Travel Forecasting Summary The Metropolitan Washington Council of Governments (MWCOG) model was used to generate traffic forecasts for the 2030 design year. The MWCOG model, which simulates transportation and land use conditions in the greater Washington DC region, encompasses more than 4,000 square miles. The model was developed to provide a basis for predicting the overall expected travel trends in future years, based on planned land‐use development and highway network scenarios at the regional level. MWCOG’s model, which uses Version 2.1D #50 of Citilab’s TP+ program, meets USEPA requirements for air quality conformity analysis. It incorporates land use assumptions from MWCOG’s Round 6.4A. The Cooperative Forecasting Program, administered by the MWCOG, enables local, regional, and federal agencies to coordinate planning using common assumptions about future growth and development in the region. Each series of forecasts, or “round,” provides land use activity forecasts of employment, population, and households by five‐year increments. Each round covers a period of 20 to 30 years. Round 6.4A represented the most recent land use forecast available at the time the travel forecasting work was carried out. DDOT obtained a copy of the MWCOG model for use in forecasting the 11th Street Bridges traffic volumes. Forecast traffic volumes from the model were used for traffic operational analyses, air quality conformity analyses, and traffic noise analyses. The traffic forecasts were used to assess and compare travel conditions under a No‐Build Alternative and each of the build alternatives. The following traffic/transportation analyses were completed for each of the alternatives: Prediction/modeling of future traffic and travel patterns Analysis of future traffic operations Comparison of access changes to key land uses or areas Analysis of travel times Evaluation of vehicular safety considerations Evaluation of impacts to pedestrians Evaluation of impacts to bicyclists Evaluation of impacts to transit operations Evaluation of impacts to freight Case Study Illustration of the Guidance The 11th Street Bridges project provides a good illustration of one of the key consideration contained in FHWA’s Guidance on the Application of Travel and Land Use Forecasting in NEPA. It was clear to the project team from the start that while MWCOG’s regional model can be effective in answering big‐picture questions, it would be ineffective, without modification, in answering such project‐specific questions as “What will be the effect of adding missing freeway connections to traffic volumes east and west of the Anacostia River?” Performing the upfront work, using the latest available data to refine the part of the regional model within the 3 project study area, convinced DDOT, FHWA, and USEPA that the team was able to credibly compare alternatives in a forecast setting. This allowed the project team to proceed through the alternatives development and refinement phase in an efficient manner and to keep the fast‐paced study on schedule. This case study emphasizes consideration 2 of the guidance: Suitability of Modeling Methods, Tools, and Underlying Data. Key Consideration 2 of the Guidance: The Suitability of Modeling Methods, Tools, and Underlying Data Age of Forecasts, Models, Data, and Methods The first travel demand model was run in 2004 under DDOT's MAC Study, before the start of the 11th Street Bridges EIS. This gave DDOT enough data to determine that the best solution to the inefficient connections between the east and west sides of the Anacostia River in the study was to reconfigure the 11th Street Bridges interchange (rather than building a flyover at Pennsylvania Avenue, which had been proposed in the past). In 2005, DDOT hired CH2M HILL to develop an EIS to evaluate replacing the 11th Street bridges and reconstructing the east‐side interchange. For the DEIS, the travel demand model was run with the 2005 version of the MWCOG model. The MWCOG model network was refined for the 11th Street Bridges Study to represent future roadway networks based on transportation projects in MWCOG’s 2004 update to the Constrained Long‐Range Plan and major projects